Railway-traffic-controlling apparatus



May 14, 1929. STQLTZ 1,712,525

RAILWAY TRAFFIC CONTROLLING APPARATUS F' iled Feb. 2, 1928 2 Sheets-Sheet l INVENTOR 2 c. F. STQLTZ 1,712,525

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed Feb. 2, 1928 2 sheeis-sneei; 2

May 14, 1929.

Patented May let, i929.

CARL STOLTZ, GTE DELHI, 015E110, AWEIGNOE TO THE TJ'NION EWI'IECH 8:; SIGNAL M PAN'Y, 03E SVTIISS'VALE, PENNSYLVANIA, A COBIPQRATION 01 PENNSYLVANIA.

RAILVJAY-TEAFFIC-CONTROLLING AIPlHARATUS Application filed February 2 1928., SerialNo. 5551,5159.

My invention relates to railway trallic controlling apparatus, and particularly to apparatus of the type intended for safely cmitrolling railway trafiic governing devices, such as switches and signals from a point remote from such devices.

I will describe oneform'of railway trallic controlling apparatus embodying my invention and will then point out the novel features thereof in claims.

In the accompanying drawings. Figs. 1 and 2 when placed end to end with Fig. 1 on the left, form a diagrammatic View showing one form of railway trallic controlling apparatus embodying my invention.

Referring to the thawing, the referenc characters 1 and 1 designate the track rails of a stretch of railway track connected with a siding by a switch 3 of the usual and well known form. The rails 1 and 1* of the main track are divided by means of insulated joints 2, to form a plurality of successive track sections A.-l3., lit-4h Cl), D lil, I lr and l tl. The rails of the siding 4: are similarly divided to form a traclrsection l-lil, the rails of the siding to the left of point 1H being connected with the rails of section D ifil in the usual manner. Each track section is provided with a track battery 5 connected across the rails adjacent one end of the section, and with a track relay connected across the rails adja cent the other end of the section and designated by the reference character R, with a suitable distinguishing exponent. Each track relay R, therefore, is normally energiaed but arranged to become de-energized when a train enters the corresponding section.

The reference character ll designates a repeater relay which is energized when relay li is closed. The circuit for relay N may l e traced from a suitable source of energy such as a battery 6 over wires 9, 10 11, 152 and 14, front contact of relay R wire 16 winding of relay N. wire 17, and common wire 18 back to battery 6'.

An approz'ich relay Y normally enerprimed by current which flows from battery 19 over wire 20, front contact EZl ofrelay lit", wire 22, front contact 23 of relay R wire 2e, front contact 25 of relay ll, wire 213., winding of relay Y, and wire 27 baclr to battx lit follows that when as east-- but that when relay Y opens, as by the en trance of a train into section A B, the circuit for relay P is interrupted as soon as relay Y opens its front contact. Due to the slow acting characteristics of relay 1, a brief interval. of time elapses after the deenergization of relay Y and prior to the opening of the front contacts of relay l The functions of relays Y and P will be explained in detail hereinafter.

v /estbound traffic from sidin 4 into the main track over the switch 3 is governed b y a signal S and westbound tra'llic through section DE is governed by a signal S. Eastbound trallic over the switch 3 is grow erned by two signals S and S, which in the form here shown are mounted upon a single mast. The circuits for controlling signals S"; S and S will be described hereinafter.

Located adjacent point B are two automatic signals S and S for governing westbound and eastbound tii'a'llic, respectively. The signals S ant S may be controlled in any suitable m nner and sine the control of these signals forms no part of my present invention, the circuits are oi'nitted from the drawing for the sake of simplicity. For present purposes it is sufficient to state that signal S is so controlled that the signal normally indicates proceed but is arran ed to indicate stop when a westbound train occupies section AB and to indicate cantion if section A B is unoccupied and the first section to the left of point A is occupied by westbound train. Signal is also placed at stop by an eastbound train when such train passes the first head block sig nal to the left of; point B, and signal 8 re mains at stop until the train has reached some point to the right of the signal.

Two signals El" and 53 are located at point for controlling eastbound trallic through section FG, These signals may be man- 7 which is provided with a circuit from battery G, througliwires 9, 10, 11,. 12, 28, 29,

'32, 33, and 34, contacti controlled by signal S, wire 36, contact 37 controlled by signal S, wire 38, contact 39 controlled by signal S wire 40, contact 41 controlled by signal S wire 42, winding of relay Q, and common wire 18 back to battery 6. It will be observed that the circuit for relay Q, contains contacts controlled by each of the sig- I tery 43.

nals govering traflic over the switch 3 and that each of these signals must be at stop in order to energize the relay Q. It will be manifest therefore, that when all of the signals associated with switch 3 are at stop, relay Q will be energized but that this relay will open if any one or more of the signals indicates caution or proceed.

Signal S is controlled in part by a line relay K which is controlled in turn by traffic conditions in advance of the signal. One circuit for relay K passes from battery 43, (Fig. 2) through wires 123, 44, 162 and 45, contact 46 controlled by signal S wire 47, pole changer a controlled by signal S, wire 48, front contact 49 of track relay R, wire 50, front contact 51 of relay N, wire 52, winding of relay K", wire 53, pole changer a-Qand wires 64-, 54, 55 and 96, back to bat- The circuit just traced is closed only when signals S and S indicate stop and when relays R and N are both energized. Under whichconditions current supplied to relay K energizes this relay in what I shall term the reverse direction so that its polar contact is swung to the left. If, however, signal S indicates caution or proceed, the pole changer a is reversed, the other parts of the circuit just traced remaining closed, and the polarity of the current supplied to relay K is then reversed. Withv signal S indicating caution or proceed, therefore, relay K is energized in the normal direction so that its polarcontact is swung to the right.

Relays K and K are connected in parallel and are at times supplied with energy through a pole changer a controlled by signal S Relay K is a neutral relay and is energized by current of either polarity, but relay K has a polar armature, which is re sponsive to the polarity of the current supplied to the relay. As shown in the drawing, signal S indicates proceed and under these conditions, current from battery 56 flows through pole changer a, wire 57, front contact 58 of relay R wire 59, front contact 60 of relay R, wire 61, front contact (52 of track relay R, wire 63, thence through windings of relays K and K in parallel, wire 65, and pole changer a back to battery 56. hen signal S indicates proceed, therefore, and when relays R, R and R are energized, relay K is picked up, and relay K is energized in such direction that its polar contact is swung to its righthand or normal position. If, however, signal S indicates stop, pole changer (I is reversed, and the polarity of the current then supplied to relays K and K is reversed, and relay K is energized in the reverse direction so that its polar contact is swung to the left.

Associated with relay K is a stick relay designated by the reference character V and provided with a pick-up circuit controlled by relay N. This pick-up circuitmay be traced from battery 6, through wires 9. 1.0. 11, 12, 28, 29, 32, and (36, back contact 67 of relay N, wire 68, contact 69 controlled by signal S, wires 70 and 71, winding of relay V and common wire18 back to battery 6. If, therefore, a westbound train enters sec.- tion DE with signal S indicating proceed or caution, the de-energization of relay N following the shunting of relay R, causes relay V to become energized. The opening of relay R" also (lo-energizes relay K, and a stick circuit is then established for relay V which passes from battery 6 over the pick-up circuit just traced as far as wire 32 and thence through wires 33, 72 and 73, back contact 74 of relay K", wire 75, front contact 76 of relay V, wires 71 and 71, winding of relay V, and common wire 18 back to battery (5. It will therefore be plain that having once been energized by the entrance of a westbound train into section D-E, relay V will subserplently be main tained in its energized condition as long as relay K is (lo-energized. It should be pointed out in this connection, however, that if signals S is indicating stop when the train enters the section, contact (39 will be open and relay V will not pick up. Furthermore, should an eastbound train approach section D-E, relay R would be dcenergized before the train reached point l). It will be explained in detail hereinafter that with relay K deenergizcd signal S indicates stop, and it follows that the entry of an east-bound train into section D-l!) cannot pick up relay V.

The switch 3, and signals S, S, S and S governing traffic over the switch, are controlled in part by a manually operable lever designated in general by the reference character L. This lever may be located at a point remote from the switch and signals lLI which it controls and maybe installed, for example, in a central despatchers office or an interlocking cabin. The lever L is capable of assuming five separate positions indicated by the dotted lines in the drawing and designated L, B, N, D, and it. The lever L controls a plurality of contacts each designated by a small circle in which are letters corresponding to the positions of the lever for which such contact is closed. For example, contacts 77, 80, and 81 are closed when the lever is between the L and B positions, and contacts 78, 79 and 82 are closed when the lever is between the H and D positions. The operation of lever L is at times controlled by a lock magnet 1&0 controlling a dog l itwhich cooperates with a locking segment 143 having! two lugs 148" and 1&3" which may engage with the locking dog 1 14.

The lever L controls a polarized relay W located adjacent the switch 3. As shown in the drawing, the lever L occupies its normal position and the relay W occupies its normal position. If the operator wishes to reverse the switch 8, he moves lever L toward the B position. Since magnet 1 10 is die-energized, the motion of the lever L is arrested at the D position by engagement of the dog 14-4: with lug 1 18'. In this position, however the LB contacts of the lever are open and the RD contacts are closed. Current then flows from battery i8, through wires 128 and 88, contact 84: of a timing device t, wire 85, contact 79 of lever L, wires 86 and. 87, winding of relay W, wires 88', 89 and .90, contact 7 8 of lever L, wires 91 and 92, contact 98 of timing device 22', and wires 94, 95 and 96, back to battery 4-8. Under these conditions, the current supplied to relay WV from battery 18, energizes relay in the reverse direction so that its polar armatures are swung to the left. The relay W controls a second polar relay T and when relay W is energized in the reverse direction, a circuit is closed from battery 6, through wires 9, 10 and 97, front contact 98 of relay K wire 99, front contact 100 of relay Y, wires 10]. and 102, front contact 108 of relay Q, wire 104, reverse contact 1.05 of relay V, wire 106, winding of relay T, wire 10?, front contact 109 of relay N, wire 110, reverse con tact 111 of relay wire 112 and. common wire 18 bacl; to battery 6. It should be observed. that the circuit just traced for relay T includes a front contact of relay Y, so that the circuit can be closed only if the track from A to D is unoccupied. Furthermore, the circuit includes a front contact of relay Q, so that the relay T can be moved from normal to reverse only if all of the signals associated with section D-E are at stop. It should also be noted that since relay N is controlled by a track relay R and since relay K is controlled by relays N and R the circuit for relay T which includes front contacts of relays N and K, can be closed only if sections D-E and EF are both unoccupied.

The switch 3 is operated. by a motor designated in general by the reference character M and comprises an armature 116 and a field 121. The motor is controlled in part by a contact device operated by the switch 8 and comprising a contact 119-119 which is closed at all times except when the switch occupies its full reverse position and a contact 119-119 which is closed at all times except when the switch occupies its full normal position. When relay T becomes energized in its reverse direction, current from battery 6 flows through wires 9, 118 and 286, reverse contact 114i of relay T, wire 115, armature 116 of motor M, wire 117, reverse contact 108 of relay T, wire 118, contact 119--119 operated by switch 3, wire 120, field 121 of motor M, and wires 122, 122 and 12 i, back to battery 6, through batteries 7 and 8 in series. When the circuit just traced is closed, therefore, the combined electromotive forces of batteries 6, 7 and 8 are applied to theficld and armature of motor M, thereby operating themotor in such direction as to shift switch 3 towards it reverse position. When the switch attains its full reverse position, contact 119--119 opens, thereby deenergizing motor M. With the switch in 15S reverse position, however, contact 134e-181 is closed and current from battery 6 then flows through wires 9, 118 and 1355, contact 184-4349, wires 136, 89, and 137, contact 82 of lever L, wires 188 and 139, winding of magnet 1 10 and wires 1 11, 141 and 142, pole changer a controlled by signal S in its stop position, and common wire 18 back to battery 6. It has already been explained that it is necessary for signal S" to indicate stop before relay T can be operated. The circuit just traced is completed,

therefore, as soon as the switch attains its reverse position, thereby energizing magnet 1 10 and withdrawing the dog 14 1 from the locking segment 148. The lever L may then be moved to its full reverse position.

If the operator wishes to restore the switch 3 to its normal position, he does so by moving the lever L toward the L position. The motion of the lever is arrested at the B position by engagement of dog 144 with lug 1418 on looking plate 143, the circuit for magnet 140 having been opened when the RD contact 82 of lever L was opened. The LB contacts on the lever L are now closed and current from battery 4L3 flows over wires 123 and 88, contact Set of timing device t, wires 85 and 125, contact 77 of lever L, wires 90, 89 and 88, winding of relay WV, wires 87 and 86, contact 80 of lever L, wire 92, contact 93 of timing device if, and wires 94:, 95 and 96, back to battery 4?). Relay W therefore swings its polar armatures to the right or normal positions. An operating circuit is now closed for relay T from battery 6, through wires 9,10, 11, 12 and 126, front contact 127 of relay R wires 128 and 129,-front contact 130 of relay Q, wire 131, normal contact 111 of relay W, wire 110, front contact 109 of relay N, wire 107, winding'of relay .T, wire 106, normal contact 105 of relay 1V, wire 132, and common wire 18 back to battery 6. The circuit just traced includes a front contactof relay Q and a front contact of relay R and it follows that relay T can be energized in the normal direction only if all ofthe signals indicate stop and section. CD is unoccupied. When relay T'is energized in the normal direction, current from batteries 6, 7 and 8 in series flows through wires 9, 113, and 236, normal contact 108 of relay T, wire 117, armature 116 of motor M, wire 115, normal contact 114 of relay T, wire 237, contact 119119 controlled by switch 3, wire 120, field 121 of motor M, and wires 122, 122 and 124, back to battery 8, The motor M is therefore operatedto move the switch 3 toward its normal. position. lVhen the switch attains its full normal position, contact 119-119 opens and discontinues the supply of energy to the motor M. With the switch in its full. normal position, magnet 140 is energized by current which flows from battery 6, through wires 9, 113 and 135, contact 134 134 operated by switch 3, wires 144 and 86,

contact 81 of lever L, wire 139, winding of magnet 140, wires 141, 141 and 142, pole changer a operated by signal S in its stop position and common wire 18 back to battery 6. Magnet 140 therefore lifts the dog 144 out of engagement with the locking segment 143 and permits the lever L to be moved to it full L position.

It has been pointed out that relay T can not be energized in its reverse direction after an eastbound train approaching the switch, has passed point A, nor can the relay be energized in its normal direction after an eastbound train, approaching the switch, has passed point C. It is desirable under some conditions to release this approach locking, so that after a train has approached the switch 3 within the limits which are defined by the approach locking, the operator of the lever L may take action to reverse the switch under proper precautions to insure the safety of trains. In my present invention this is accomplished by a relay X which may be energized to close a branch for the circuit of relay T under predetermined conditions. One pick-up circuit for relay X is controlled by the timing device 23 located adjacent the lever L. The timing device if may be a clock work time release of the usual and well knownform and, comprises a handle which normally occupies the position shown in the drawing in which contacts 175, 172, 84 and 93 of the device are closed. \Vhcn the timing device is operated, certain other contacts 151 and 146 are closed and when the device is released a measured interval of time elapscs before the device returns to its initial condition. When the timing device t is operated, current from battery 43 is supplied to relay X over a circuit which passes through wires 123, 83 and 145. contact 146 of timing device t, wire 147, front contact 148 of relay Q, wire 149, winding of relay X, common wire 18 to pole changer u. and thence through wires 142, 141" and 150, contact 151 of timing device t, and wires 152, 95 and 96, back to battery 43. If, therefore, relay Q is energized when timing device t is operated, relay X is picked up. llaving once been energized, relay X only subsequently be held in its energized condition as long as relay Q remains energized. by current from battery 6, which llows over a circuit through wires 9, 155, 165 and 156, front contact 157 of relay X, wires 158 and 159, front contact 160 of relay Q, wire 161. front contact 148 of relay Q, wire 149, winding of relay X and common wire 18 back to battery 6. Relay X, having once been energized to close its stick circuit, held in its energized condition until one of the signals associated with section D-E is cleared to (lo-energize relay Q.

When relay X is energized, if relay W occupies its normal position, a shunt is closed around front contact 127 of relay R in the circuit for relay T, so that the circuit for this relay may now be traced from battery 6, through wires 9, 155 and 165, front contact 163 of relay X, wires 164 and 129, front contact 130 of relay Q, wire 131. normal contact 111 of relay \V, wire 110, front contact 109 of relay N, wire 107, winding of relay T, wire 106, normal cont act 105 of relay V, wire 132, and common wire 18 back to battery 6. If, therefore, relay X is energized to release the approach locking, energization of relay \V in the normal direction will energize relay T in the normal dircction provided only that all of the signals associated with section -l) indicate stop and the section is unm-cupicd. In similar manner, it should be observed that when relay X energized front contact 100 of relay V and front contact 98 of relay K are shunted out of the rewrse operating circuit for relay T so that if relay \V is energized in the reverse direction, a circuit is closed for relay T from battery 6, through wires 9 and 155, front contact 166 of relay X. wires 167 and 102, front contact 103 of relay Q, wire 104, reverse contact 105 of relay 1V, wire 106, winding of relay T, wire 107, front contact 109 of relay N, wire 110, reverse con tact 111 of relay W, wire 112 and common wire 18 back to battery 6. It follows, therefore, that if relay W is reversed when relay X is closed, relay T is swung to the reverse position to reverse switch? provided only that all of the signals associated with section lD- l l are at stop and the section is unoccupied.

It is sometimes desirable to inform the operator in charge of lever L when a train passes point A, because when a train passes this point, relay Y becomes de energized and it is then necessary to operate the timing device t to move the switch from normal to reverse. it is also desirable to inform the operator when a train enters section D--E. This information is given to the operator by means of a lamp 184 which is controlled by an indication relay Z. When relay Z is energized, current from battery 13. flows through wires 123, 1 1 and 238, front contact 182 of relay Z, wire 183, lamp 184 and wires 108, and 96 to light the lamp 184. Relay Z is arranged to be energized for a brief interval when an eastbound train passes point A, the operation being as follows:

lVhen the train enters section 1iB, relay it becomes de-energized, thereby de-cnergising relay Y. This relay immediately drops, and breaks the circuit for relay P. As has already been explained, a time inter- "al elapses after the deenergization of relay Y and prior to the opening of front contact 180 of relay P. During this brief time interval, current flows from battery 6, through wires 9, 10, 11,12, 28 and 177, back contact 178 of relay Y, wire 179, front contact 180 of relay P, wires 181, 1 17 and 171, contact 172 of timing device t, wire 17 3, winding of relay Z, wire 17%, contact 175 of timing device 25, wires 176, 150, l ll and 141-2, pole changer a operated by signal S, and commen wire 18 bach: to battery 6. It will be plain from the foregoing that when a train passes point A, relay Z becomes energized. soon as relay P releases its :tront contact 180, the circuit just traced for relay Z is interrupted, and the relay then becomes deenergized. The lamp 184 is, therefore flashed for a brief interval of time to indicate to the operator of lever L that a train has passed point A.

Another circuit is provided for relay Z which may be traced from battery 0, through wires 9, 10, 11 and 168, back contact 169 of relay R wires 170 and 159, front contact 100 of relay Q, wires 101, 1 17 and 171., ccn tact 172 of timing device 25, wire 178, winding of relay Z, wire 174, contact 175 of timing device 25, wires 176, 150, 141 and 14-2, pole changer a controlled by signal S, and common wire 18 back to battery 6. When the train enters section D-E, therefore, relay it will be (ls-energized, and if relay Q, is ener ized, current will then be supplied over the circuit just traced to hold relay Z in its energized condition. hen lamp 1.8 1

is continuously energized, therefore, the operator is informed that a train occupies sec tion D-E.

l/Vhen signal S indicates caution or proceed,

the pole changer a controlled thereby, occupies the position in which it is illustrated in the drawing. Under these conditions, current from battery 7 flows through common wire 18 to pole changer a, thence through wire 199, front contact 198 of relay R, wire 197, winding of relay K w? "es 198 and 1 12, pole chai'iger (0, wires 158 and 105, front contact 19a of relay K, wire 108, contact 192 of circuit controller U operated by switch 3, wire 191, normal contact 190 of relay W, wire 189, front contact 188 of relay wire 187, front contact 186 of relay N, and wire 185 back to battery 7 \Vhen this circuit is closed, relay K is energized in the normal direction so that its polar contact is swung to the right. If signalth" at stop, however, so that pole changer a is reversed, the circuit for relay K may be traced from battery 0, through wires 9, 10, 11, 12, 28, 29, 82, 33, 72 and 73, front contact 200 of relay K, wires 21. 1- and 201, pole chari a, wire 199, front cont ct 198 of relay lit, wire 197, winding of relay K wires 190 and 142, pole changer a and common wire 18 bacl: to battery 6. Vi hen this circuit is closed, relay 1'? is energized in the reverse direction so that its polar armature swung to the left. i

The sigi'ial is controlled in accordance with the position of relay K by virtue of circuits which I will now describe. One circuit for signal S may be traced from battery 18, through wires 128 i, 162 and 202, front contact 208 of relay E wire 20a, switch r, wire 205, front contact 206 of r lay K wire 207, operating mechanism of signal E3 and wires 208, 5d, and 96, back to battery 48. It will be plain therefore that when the switch '2' is closed, and when relay K energized, the circuit ust traced for signal S is closed and under these conditions the signal indicates caution. if switch 0* is closed when relay K energized in the normal direction, current flows from battery 13, through wires 128, l-Ll, 162 and 202, front contact 203 of relay R wire 20 1:, switch 9, wire 205, front contact 200 of relay K wire 209, normal contact 210 of relay K wire 211, operating mechanism of signal S and wires 208, 54,-, 55 and 90 back to battery d8. l/Vhen this circuit is closed, signal S indicates proceed. lVl'ien relay K is de-energized or when the switch r open, both the operating circuits for signal S are open and the signal indicates stop. In actual practice, the switch r controlling signal S isusually interlocked with the apparatus which con- ,186' of relay N,

trols signals S and S to prevent clearing of signals for conflicting routes at. the same time.

is As shown in the drawing, the track is unoccupied and signals S and S both indicate stop and lever L occupies its L position. Relays W and T are energized in their normal directions and switch 3 occupies its normal position. All of the track relays are energized and relays K, K and K re energized in their normal directions, but re lay K is energized in its reverse direction because pole changer a controlled by signal S is reversed. An operating circuit for signal S is now closed. from battery 8, through wire 185, front contact 186 of relay N, wire 187, front contact 188 of relay W,

wire 189, normal contact 190 of relay 1V,

wire 191, contact 192 of circuit controller U, wire 215, front contact 216 of relay K, wire 217, operating mechanism of signal. S, and wires 122 and 124 back to battery 8. The circuit just traced is provided with a branch which passes from front contact 210 of" relay K through wire 218, normal contact. 219 of relay K wire 220, operating mechanism of signal S, and wire 124 back to battery 8. This branch is new open, however, because relay K is energized in the reverse direction and under these conditions signal S indicates caution.

A circuit for signal S may be traced from battery 8, through -wire 185, front contact wire 187, front contact 188 of relay 1V, wi e 189, normal contact 190 of relay W, wire 191, contact 192 of circuit controller U, wire 193, front contact 194 of relay K, wires 195 and 221, operating mechanism of signal S, and wires 222, 122

and 124, back to battery 8. When this circuit is closed, signal S indicates caution. The circuit gust traced for signal S is pro- 1 vided with a brancn from. front contact 194 of relay K, through wire 223, normal contact 224 of relay "K wire 225, operating mechanism of signal 6 towire 222. This branch is now closed because relay K is energized 1n its normal direction and signal S? therefore indicates proceed. Signals S and S indicate stop.

If now, the operator wishes to reverse switch3, he'mov'esthe leverL to the D position as has been described hereinbefore. Relay 1V first becomes (lo-energized and then becomes energized in the reverse direction. As a result the operating circuits for signals S and S are interrupted and these signals go to stop. WVil'h all. the signals associated with section DE now indicating stop, relay Q picks up, whereupon relay T becomes energized in the reverse direction to reverse switch 3. 1V hen the switch 3 has; reached its full reverse position, circuit controller U reverses, and. signal S moves to the caution position, its operating circuit being closed from battery 8, through wire 185, front contact 186 of relay N, wire 187, front contact 188 of relay W, wire 189, reverse contact 190 of relay \V, wire 226, contact 227 of circuit controller U, wires 228 and 229, operating mechanism of signal S, and wire 124 back to battery 8. The circuit just traced is provided with a branch which passes from wire 228, through wire 230, back contact 231 of relay R, wire 232, front contact 233 of relay K, wire 234, operating mechanism of signal S, wires 235, 222, 122 and 124 back to battery 8. This branch just traced includes a back contact of relay R and the signal S therefore indicates stop until a train enters a section HJ. whereupon relay R drops, to complete the branch just traced, causing signal S to indicate proceed. In similar manner, if the operator restores lever L to its L position, the de-energization of relay V interrupts the circuit for signal S, and also for signal S' should this signal be cleared, and when relay next becomes energized in the normal direction, relay T becomes energized in its normal direction to restore switch 3 to its normal direction. \Vhen this occurs, the signal S returns to its caution position and signal S returns to proceed position.

\Vith the parts occupying the positions in which they are illustrated in the drawing, I will next assume that a train moving from west to east, passes point A. As a result, relay Y becomes de-cnergized. If, now, the operator attempts to reverse switch 3 by moving lever L toward its R position, relay V will become energized in its reverse direction, and thereby set all of the signals associated with section D-E at stop, but the circuit for relay T is now open at front contact 1.00 of relay Y and the switch can not be reversed. It should also be poinIcd out that at the instantv the train entered sec tion A-B, relay Z became energized for a brief interval to flash. lamp 184, thus informing the operator that the approach locking has been effective. Under these conditions, if the operator wishes to reverse the switch, he may do so by operating the timing device t. hen this occurs, relay X beconu-s ener ized and is subsequently held in its euergized condition as long as relay Q, is closed. It should be pointed out, however, that upon operation of device f, contacts 84 and 93 are opened, and that these contacts do not close again until after the expiration of a time interval following the operation of the device. During this time interval, it

is impossible for current to be supplied to relay so that this relay is (lo-energized and reversal of the switch 3 is prevented until the contacts 84 and 93 of device t are again closed. Furthermore, while device t is being operated, the relay Z is disconnected from wire 147, so that the energy which is supplied to wires 147 and 150 to energize relay X can not actuate relay Z to give a false indication to the operator. After the timing device t has returned to its normal condition, the operator may reverse the switch 3 by proper manipulation of lever L, the opera tion of the apparatus in response to the consequent reversal of relay Wbeing readily understood from the foregoing explanation.

I will now assume that the switch occupies its reverse position and that the train occupies section A-B or 13- 0. Relay Y is tie-energized but no contact of relay Y is involved in that circuit for relay T which energizes the relay in its normal direction. it follows that the operator may move switch 3 to its normal position by operating-lever L to its L position at any time prior to the entry of the train into section C D. If, however, the train is actually in section U D, relay R is de-energized and contact 127" is therefore open. It the operator now moves lever L toward its L position in an attempt to restore the switch to its normal position, the relay V7 will become energized in its normal direction. but since the circuit for relay T is now open at front contact 127 of relay R the operation of the switch is prevented. Even with the train occupying section CD, however, the operator may reverse the switch it he releases the approach locking by operation of the timing device If. it this occurs, relay X picks up and a branch closed for the circuit of relay T,through liront contact 163 of relay X around front contact 127 of relay R When the timing device t returns to its original condition, therefore, relay W again picks up and relay T swings to its normal position to restore the switch to its normal position. It should be pointed out that it a train occupying section D E, relay N is tie-energized so that front contacts 109 and 186 are open. Under these coi'iditions, the circuit for relay T 3'. open so that this relay becomes de-energized, opening the operating circuit for motor hi. it follows that it is impossible to actuate the switch 8 when any portion of a train occupies the section DE.

The operator may place at stop all the signals associated with section D-E at any time by simply moving lever L to its N position. This opens all contacts of the lever and tic-energizes relay W, thereby interrupt ing at front contact 186, all circuits for signals S", S, S and S.

For purposes of simplicity, I have illustrated apparatus for accomplishing approach locking of the switch 3 only in response to trains approaching the switch from the west but it should be distinctly understood that I do not wish to be limited to apparatus of this scope but that similar apparatus could be provided for accomplishing approach looking for westbound traiiic.

Although I have herein shown and described only one form of railway tratlic con trolling apparatus embodying my invention, it is understood. that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope o'l" my invention.

Having thus describedmy invention, what I claim is:

1. In combination, a railway switch, a manually controlled lever, a first polarized relay controlled by said lever, a second polarized relay, means responsive to trailic conditions for at times energizing said second polarized relay in one direction or the other according as the first polarized relay is energized in one direction or the other, and a motor controlled by said second polarizedrelay for moving said switch to its normal or reverse position according as said second polarized relay is energized in one direction or the other.

'2. In combination, a railway switch, a manually controlled lever, a first polarized relay controlled by said lever, a normally energized approach relay arranged to be (leenergized when a train moving in one direction approaches said switch, a second polarized relay controlled by said first polarized relay and by said approach relay, and a motorcontrolh-zd by said second polarized relay for operating said switch.

3. In combination, a railway switch, manually controlled lever, a first polarized relay controlled by said lever, a first contact arranged to be opened when a train approaching said switch passes a definite point, a second contact arranged to be opened when a train approaching said switch passes a different point, a second polarized relay, means including said first contact and a normal contact of said first polarized relay for energizing said second relay in the normal direction, means including said second contact and a reverse contact of said first relay for energizing said second relay in the reverse direction, and a motor for moving said switch to its normal or reverse position according assaid second relay is energized in the normal or reverse direction.

4. In combination, a railway switch, a manually controlled lever, a first polarized relay controlled by said lever, a normally energized approach relay arranged to be deenergized when a train moving in one direction approaches said switch, a second polarized relay controlled by said first polarized relay and by said approach relay, a manually operable timing device, means controlled by said timing device for removing said approach relay from the control of said second polarized relay, and a motor controlled by said second polarized relay for operating said switch.

/In combinatioma railway switch, a

manually controlled lever, a first polarized relay controlled by said lever, a stick relay, a first contact arranged to be opened when a train approaching said switch passes a definite point,.a second contact arranged to be opened when a train approaching said switch passes a different point, a second polarized relay, means including said first contact and a normal contact of said first polarized relay for energizing said second relay in the normal direction, a branch around said first contact including a front contactof said stick relay, means including said'second contact and a reverse contact of said first relay for energizing said second relay in the reverse direction, a branch around said second contact including a front contact of said stick relay, a manually operable timing device, a pick-up circuit for said stick relay controlled by said timing device,

its normal position, a manually operable lever, a first polarized relay controlled by said lever whensaid timing device occupies its initial position, a normally energized relay arranged to be de-energized when a train is approaching said switch, a second polarized relay controlled'by said normally energized relay and by said first polarized relay,

means" set into operation when said timing device Isactuated and continuing after said timing device returns to its initial position to remove said normally energized relay from the control of said second polarized relay, and a motor controlled by said second polarized relay for operating said switch.

7. In combination with a railway switch, a manually operable lever, a first polarized relay controlled by said lever, a second polarized relay controlled by said first polarized relay and by trafiie conditions ad jacenl the switch, a motor controlled by said second polarized relay for actuating said switch, a signal relay controlled by traliic conditions adjacent the switch, and a signal controlled by said signal relay and by said lirst polarized relay for governing trallic over said switch.

8. In combination with a railway switch, a manually operable lever, a first polarized relay controlled by said lever, a normally closed contact arranged to be opened when a train apln'oaching said switch, passes a definite point, a second polarized relay controlled by said contact and by said first polarized relay, a motor controlled by said second polarized relay for actuating said switch, a. signal relay, a circuit for said signal relay controlled by trallic conditions adjacent the switch, a signal controlled in part by said signal relay for governing lrallic over said switch, an indication relay adjacent said lever, means including a portion of the circuit for said signal relay for energizing said indication relay when a train passes said point, a lamp controlled by said indica' tionrelay, and manually operable means for at times removing said contact from the control of said second polarized relay.

In testimony whereof I afiix my signature.

CARL F. STOLTZ. 

